A179264 Number of permutations of 1..n with sum (i-p(i))^2 <= (n+1)*n/2.

1, 2, 5, 13, 41, 151, 672, 3047, 13796, 70702, 406241, 2306597, 13050503, 81009240, 546463298, 3646507024, 24169492053, 172363021094, 1313445510576, 9904229155933, 74120163086669

Offset

1,2

Links

Table of n, a(n) for n=1..21.

Crossrefs

Cf. A179266.

Sequence in context: A149868 A343175 A007269 * A096724 A088553 A262934

Adjacent sequences: A179261 A179262 A179263 * A179265 A179266 A179267

Keyword

nonn

Author

R. H. Hardin, Jul 06 2010

Status

approved